The Astronomers of the University of Maryland in the United States and the University of Tokhoku in Japan offered a new explanation, why Mercury has a large core compared to the mantle. It was previously assumed that the cause of the anomaly became frequent collisions with other cosmic bodies in the early stages of the existence of the solar system, as a result of which most of the mantle was destroyed. However, the new model shows that it is not. The mystery of the mystery of the core formation closest to the sun planet is told in the magazine Progress in Earth and Planetary Science.
Scientists have shown that the density, weight and iron content in the core of the rocky planet depends on the remoteness of its orbit from the magnetic field of the Sun. According to astronomers, there is a gradient in which the metal content in the kernel falls with the distance of the planet from the parent star. In the early solar system, when the young sun was surrounded by a dust and gas cloud, iron particles attracted to the center of the magnetic field of the sun.
When an early solar system began to cool, dust and gas that did not get into the sun, began to slip. The clots located closer to the Sun were exposed to a stronger magnetic field and, thus, contained more iron than those that were further from the Sun. When the clots merged and cooled, forming rotating planets, iron lowered to the kernel.
When the researchers used this model to calculate the content of metals and density in modern planets, they found that predicted gradients correspond to the observed picture. Mercury has a metallic core, which is about three quarters of its mass. The cores of the Earth and Venus constitute only about one third of the total mass of the planet, and Mars, the most remote from the stony planets, has a small kernel, which is only about a quarter of its mass.
To confirm the new hypothesis, scientists need to find another planetary system with rocky planets located at large distances from the parent star. If the density of the planets will fall with a distance, as happens in the solar system, the researchers will be able to make the final conclusion that the magnetic field of the star affects the formation of the planets.